Process of veneering boardlike material



May 8, 1929. A. ELMENDORF 1, ,858

PROCESS OF VENEERING BOARD LIKE MATERIAL Filed July 11, 19 27 Patented May 28, 1929.

ARMIN Euumvnom', or CHICAGO, ILLINOIS. v

PROCESS OF VENEERING BOARlDLIKE MATERIAL.

Application filed July 11,

. gluing, but must be allowed to stand to permit the glue to set.

, Generally speaking, the objectrof the present invention is to improve the process of my aforesaid patent. Viewed in one of its aspects the present invention may be said to have-for its object to prevent the glue from striking through the veneer in the process of gluing the latter to a core. Viewed in another of its aspects, the present invention may be said to have for its object to produce the veneered product in a single operation so that it will immediately be ready for use without delayin while the glue sets.

The various fbatures of novelty whereby my invention is characterized will hereinafter he pointed out with particularity in the claims; but, for a full understanding of my invention and of its objects and advantages, reference may be had to the following detailed description taken in connection with the accompanying drawing, wherein:

Figure 1 is an edge view of a fragment of a veneered core; and Fi 2 is a schematic view of an apparatus by w ich my improved 0 process may be practiced.

Referring to Fig. 2 of the drawing, A represents a board-like core of any suitable material that will usually consistwholly or partially of-pulp, faced on both sides with thin veneer as indicated at B and C. This veneer, as explained in my aforesaid patent should be thin enough to prevent checking or cracking when it is dried while held against contraction.

In carrying out my invention in such a way as to secure all of the advantages thereof, I employ a dry glue, that is, the core is coated on both faces with glue and the latter is then dried before the veneer is applied. The moisture necessary to make the glue tacky is then supplied by the moisture content of the veneer. By regulating the initial moisture content of the veneer and the temperature and time element in drying, the glue will not become fluid enough to strike through the veneer.

1927. Serial N'o. 204,936.

In Fjg. 1 of the drawing 1 have shown a convenientmeans for practicing my inventron. The veneer may be supplied in rolls B, B and C, C mounted respectively above and below a pairof pressure rollers 1 and 2. The core member A, having on both faces a dry glue coating, may be fed across a table 3 between the rollers 1 and 2, the veneer B entering between the rollers above the core and the veneer C below the core. The veneers are pressed against the core as they pass through the first set of rollers further pressure being subsequently applied by additional sets of rollers of which only two, 4 and 5 and 6 and 7, are shown. .The rollers may be heated or dry heated air ma be caused to flow over the "eneered boar in the spaces between the sets of rolls to dry the board. At the beginning of the process some of the moisture in the veneers will be driven through the faces in contact with the glue by the heat and pressure, softening the glue and causing itto adhere to the veneers. Thereafter both the glue and the veneers will be dried, with the result that at the end of the process a finished product remains.

When the veneer is stuck to the core, the

latter being practically rigid, the veneer is held by the core against contracting as it normally would upon drying, the elasticity of the thin veneer permitting it to make internal adjustments such that no checking or cracking occurs during drying.

If the veneers do not initially contain the necessary amount of moisture, moisture may be supplied thereto, preferably at the beginning of the process. To this end water reservoirs 8 and 9 may be placed in front of the pressure rollers 1 and 2, these reservoirs containing rollers 10 and 11, respectively, that dip into the water and engage with the veneers before the latter pass between the pressure rollers.

It will thus be seen that my process is extremely flexible, permitting the moisture content of the veneer, the temperature of the .rollers or drying air or both, and the speed at which the process is carried out to be varied within wide limits to suit the characters of the veneer and the glue in any given case. It will also beseen that at the end of the'process the product is ready for immediate shipment or use.

While I have explained my invention with particularity I do not wish to be limited to all of the specific details that have been set forth; but intend to. cover any process coma constituting the appended claims.

I claim:

1. The process of facing a stifi core memher with veneer, which consists in coating the core member with a liquid adhesive which will become tacky when moistened after having been dried, drying the adhesive, laying onthe dry adhesive wood veneer containing a large amount of moisture, and pressing the veneer against the core member, the pressure and the temperature being so predetermined that suflicient moisture will be transferred from the veneer to the adhesive to render the latter tacky but not enough to render it liquid.

2. The process of producing a stiff core faced with veneer so thin that no checking or cracking will occur in one face while the other face is held against contraction, which consists in coating the core member with a liquid adhesive that will become tacky when moistened after having been dried, drying the adhesive, laying on the adhesive a layer of said veneer containing a large amount of moisture, and applying to the veneer pressure and heat such as to drive sufficient moisture from the veneer to render the latter tacky but not liquid and subsequently dry the veneer and set the adhesive.

In testimony whereof, I sign this specification.

ARMIN ELMENDORF. 

